Driving device and vacuum device

Abstract

To provide a driving device and a vacuum device capable of reducing the time required for a moving body to stop moving after starting a predetermined moving operation as compared to conventional methods.SOLUTION: A driving device 10A used in a vacuum device 1 includes a driving member 14A connected to a moving body 3A, a stepping motor 11, a power transmission unit 20A, a control unit 13 that controls the stepping motor 11, and an encoder 18A that transmits stopping position information of the driving member 14A to the control unit 13. The control unit 13 performs a pulse number updating process to change the set number of driving pulses based on the stopping position information.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a drive device that moves a moving body arranged in a high vacuum environment, and a vacuum apparatus including the drive device. [Background technology]

[0002] Vacuum devices are used in the manufacturing processes of various products such as semiconductors and flat panel displays. These vacuum devices perform a predetermined process on a processing object in a vacuum environment. In such vacuum devices, generally, a robot that transports the processing object, a holding device that holds the processing object, and the like perform predetermined operations with high precision to move the processing object.

[0003] Furthermore, the vacuum device generally includes a drive device that drives a moving body that is a part of the above-mentioned robot, holding device, etc. and moves in a predetermined manner within the device. Such a drive device may be required to stop the moving body at a predetermined position with high accuracy when moving the moving body.

[0004] When high positioning accuracy is required for a drive device that moves a moving body placed in a vacuum environment, feedback control is generally adopted in which a sensor detects the stop position of the moving body and the drive device is driven again based on the detection result. An example of a drive device that performs such feedback control is the drive mechanism disclosed in JP 2023-067381 A.

[0005] This drive mechanism is a device for rotating a holder that holds a substrate to be irradiated with an ion beam, and includes a first shaft member connected to the holder, a servomotor, and a plurality of transmission gears arranged between the first shaft member and the servomotor. This drive mechanism also includes an external encoder that detects the rotation angle of the first shaft member, and the servomotor is controlled based on the rotation angle detected by the external encoder. In this drive mechanism, a part of the first shaft member, the transmission gear, the servomotor, and the external encoder are housed in a single casing and placed in an atmospheric pressure environment.

[0006] In this drive mechanism, an external encoder detects the rotation angle of the first shaft member at a position close to the holder in a power transmission path that transmits the power of the servo motor to the holder, so that this drive mechanism can position the holder with high precision.

[0007] However, with this drive mechanism, for example, if the backlash of the transmission gear is large, feedback control is repeatedly applied to the servo motor before the rattling of the transmission gear is resolved, and it takes time for the first shaft member to converge to the stop position.

[0008] It is also possible to use a pulley and a rubber belt instead of a transmission gear to transmit the power of the servo motor to the holder, but in this case, it takes time for the first shaft member to converge to the stop position due to the elasticity of the rubber belt, just as in the case of using a transmission gear. And because this drive mechanism uses a servo motor, the faster you try to stop the holder, that is, the faster you try to stop the first shaft member, the longer it takes to stop the first shaft member, and there is a risk of a hunting phenomenon occurring. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Patent Publication No. 2023-067381 Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention aims to provide a drive device and a vacuum device that can precisely control the position at which a moving body is stopped and can reduce the time required for the moving body to stop after starting a specified movement operation compared to the conventional devices. [Means for solving the problem]

[0011] The driving device of the present invention is used in a vacuum device that performs a predetermined process on a processing object, and is a driving device that moves a moving body arranged in a vacuum environment so that the moving body performs a predetermined moving operation, the driving device comprising: a driving member that is directly or indirectly connected to the moving body and moves the moving body; The actuator comprises a stepping motor that outputs power to drive the driving member, a power transmission unit that is interposed between the stepping motor and the driving member and transmits the power from the stepping motor to the driving member, a control unit that controls the operation of the stepping motor, and an encoder that acquires stop position information related to the position where the driving member stops as the stepping motor stops and transmits the stop position information to the control unit, and is configured such that the control unit can input a pulse signal having a number of drive pulses that is preset as the number of pulses required for the movement operation to the stepping motor to operate the stepping motor, and then perform a pulse number change process that changes the set number of drive pulses based on the stop position information.

[0012] According to this configuration, the driving device uses a stepping motor and operates the stepping motor by inputting a pulse signal having a predetermined number of driving pulses as the number of pulses required for the moving operation to the stepping motor. Therefore, the driving device of the present invention can stop the driving member driven by the power of the stepping motor at a predetermined position or within a predetermined range with high accuracy. As a result, the moving body connected to the driving member is also stopped at a predetermined position or within a predetermined range with high accuracy. In addition, since the driving device of the present invention employs a stepping motor, even if there is a rattle or the like in the power transmission unit, the driving member can be stopped in a short time compared to the case of using a servo motor. Furthermore, the control unit can perform a pulse number changing process to change the set number of drive pulses based on the stop position information transmitted from the encoder. Therefore, even if the moving operation of the moving body is repeated and the stop position of the drive member is considered to change over time due to, for example, wear or deformation of the parts that make up the power transmission unit, the drive member can be stopped at a predetermined position or within a predetermined range with high accuracy.

[0013] In addition, the driving device of the present invention is configured so that, after the control unit operates the stepping motor, it selects and performs one of a plurality of controls depending on the stop position information, including at least a first control which determines that the driving member has stopped within a predetermined range and determines that the pulse number change processing is unnecessary, and causes the driving member to maintain a stopped state, and a second control which determines that the driving member has stopped within the predetermined range and determines that the pulse number change processing is necessary, causes the driving member to maintain a stopped state, and performs the pulse number change processing.

[0014] In this configuration, the control unit selects and performs one of a plurality of controls, including a first control and a second control, in response to the stop position information transmitted from the encoder. For example, even if the stop position of the driving member is within a predetermined range, if it is estimated that the driving member is likely to stop outside the predetermined range in the next or subsequent operation, the second control, which performs a pulse number change process, is executed. This allows the driving device to continue to ensure high positioning accuracy.

[0015] Moreover, the driving device of the present invention may be configured such that the moving body is a holding device that holds the object to be processed, and the moving operation is an operation of moving the holding device holding the object to be processed to a position where the processing is performed.

[0016] According to this configuration, the predetermined processing is performed on the processing object while the processing object is positioned with high accuracy.

[0017] The drive device of the present invention may be configured such that the power transmission unit has a power transmission member that transmits the power, and the power transmission member has elasticity.

[0018] When the power transmission member is elastic, if a conventional servo motor is used, it takes time to converge the stop position of the drive member. In contrast, with this configuration using a stepping motor, it is possible to stop the drive member within a predetermined range in a shorter time than in the past, even if the power transmission member is elastic.

[0019] The vacuum apparatus of the present invention is a vacuum apparatus that performs a predetermined process on a processing target, comprising a drive device that moves a moving body arranged in a vacuum environment so that the moving body performs a predetermined moving operation, and the drive device comprises: a drive member that is directly or indirectly connected to the moving body and moves the moving body, a stepping motor that outputs power to drive the drive member, a power transmission unit that is interposed between the stepping motor and the drive member and transmits the power from the stepping motor to the drive member, a control unit that controls the operation of the stepping motor, and an encoder that acquires stop position information related to a position where the drive member stops as the stepping motor stops and transmits the stop position information to the control unit, and the control unit is configured to input a pulse signal having a drive pulse number that is preset as the number of pulses required for the moving operation to the stepping motor to operate the stepping motor, and then perform a pulse number change process that changes the set drive pulse number based on the stop position information. Effect of the Invention

[0020] According to the driving device and vacuum device of the present invention, the position at which the moving body is stopped can be controlled with high precision, and the time required for the moving body to stop after starting a predetermined movement operation can be shortened compared to the conventional art. [Brief description of the drawings]

[0021] [Figure 1] 1 is a schematic diagram showing an overall configuration of a vacuum apparatus (ion beam irradiation apparatus) having a driving device in a first embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic diagram showing the configuration of a drive device in the embodiment. [Diagram 3] FIG. 4 is a side view showing a state in which the movable body (substrate holding device) in the embodiment is at an initial position. [Figure 4] FIG. 4 is a side view showing a state in which the movable body (substrate holding device) in the embodiment is at a stop position. [Diagram 5]6 is a graph showing the relationship between the movement amount and the irradiation angle in the embodiment. [Figure 6] FIG. 6 is a schematic diagram showing a configuration of a drive device according to a second embodiment of the present invention. [Figure 7] FIG. 13 is a schematic diagram showing the configuration of a drive device according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] An embodiment of the present invention will be described with reference to Figures 1 to 7. Note that Figures 1 to 7 are all created for the purpose of understanding the present invention, and the shapes and length ratios of the components in each figure are not necessarily consistent.

[0023] First, a first driving device 10A in a first embodiment of the present invention and a vacuum device 1 including the first driving device 10A will be described. The vacuum device 1 is an apparatus that performs a predetermined process on a processing target T in a vacuum environment. As shown in Fig. 1, the vacuum device 1 includes a first vacuum chamber 2A, the inside of which is a high vacuum environment, and a first moving body 3A that is disposed in the first vacuum chamber 2A and is driven to perform a predetermined moving operation. The vacuum device 1 also includes a first driving device 10A that drives the first moving body 3A so that the first moving body 3A moves in the predetermined moving operation. The first driving device 10A includes a main body 12 that houses a stepping motor 11 therein, and a control unit 13 that controls the operation of the stepping motor 11.

[0024] A commonly known stepping motor is used as the stepping motor 11 in this embodiment, and the amount of rotation output by the stepping motor 11 is proportional to the number of pulses of the input pulse signal.

[0025] The inside of the main body 12 is in an atmospheric pressure environment, and the main body 12 is disposed inside the first vacuum chamber 2A in an airtight state. In addition, the control unit 13 in this embodiment is disposed outside the first vacuum chamber 2A. The control unit 13 may be disposed inside the main body 12, and the location where the control unit 13 is disposed is not limited to a specific location.

[0026] The vacuum device 1 further includes a first interlocking body 4A that is controlled to operate in conjunction with the first moving body 3A performing a predetermined moving operation, and an equipment control unit 5 that controls the first interlocking body 4A based on a signal received from the control unit 13. The equipment control unit 5 in this embodiment controls the operation of the vacuum device 1, and controls the operation of the first interlocking body 4A as part of the control of the vacuum device 1.

[0027] In the vacuum device 1, the control unit 13 first transmits a pulse signal to the stepping motor 11 to drive the stepping motor 11. When the stepping motor 11 receives the pulse signal and drives it, the power output by the stepping motor 11 is transmitted to the first moving body 3A, and the first moving body 3A performs a predetermined moving operation. After that, the control unit 13 selects and performs one of a first control, a second control, and a third control, which will be described later, based on the position where the first moving body 3A stops after performing the predetermined moving operation.

[0028] When the control unit 13 determines that the first moving body 3A has stopped within a predetermined range, it performs the first control or the second control described below, and sends an authorization signal to the device control unit 5 to permit the operation of the first interlocking moving body 4A.

[0029] Furthermore, when the control unit 13 determines that the first moving body 3A has not stopped within the specified range, it performs a third control, which will be described later, and drives the stepping motor 11 again so that the first moving body 3A stops within the specified range, and again determines whether the first moving body 3A has stopped within the specified range.

[0030] When it is determined that the first moving body 3A has stopped within a predetermined range and the device control unit 5 receives a permission signal from the control unit 13, the device control unit 5 operates the first interlocking operating body 4A.

[0031] The vacuum apparatus 1 in this embodiment is an ion beam irradiation apparatus that irradiates an ion beam IB onto a processing object T in a vacuum environment, for example, an ion implantation apparatus used in a semiconductor manufacturing process. The processing object T in this embodiment is a wafer.

[0032] The vacuum apparatus 1 in this embodiment includes an ion source 6 in which plasma is generated, and a beam transport path 7 that mass-separates and transports an ion beam IB extracted from the ion source 6. The beam transport path 7 is connected to a first vacuum chamber 2A, and the ion beam IB is guided into the first vacuum chamber 2A.

[0033] The first vacuum chamber 2A in this embodiment is a processing chamber in which an ion beam IB is irradiated onto a processing object T, which is a wafer. The first moving body 3A in this embodiment is a holding device that holds the processing object T, which is a wafer. The first interlocking moving body 4A in this embodiment is a part of a transport device that transports the first moving body 3A. To facilitate understanding of this embodiment, hereinafter, the vacuum device 1 may be referred to as the ion beam irradiation device 1, the first vacuum chamber 2A as the first processing chamber 2A, the processing object T as the wafer T, and the first movable body 3A as the holding device 3A. Therefore, hereinafter, the ion beam irradiation device 1, the first processing chamber 2A, the wafer T, and the holding device 3A may be read as the vacuum device 1, the first vacuum chamber 2A, the processing object T, and the first movable body 3A, respectively.

[0034] Inside the first processing chamber 2A, there are disposed a holding device 3A capable of holding a wafer T, and a main body 12 of a first driving device 10A that drives the holding device 3A so that the holding device 3A performs a predetermined movement operation.

[0035] In this embodiment, the first driving device 10A drives the holding device 3A to rotate the holding device 3A about the first rotation axis A1 shown in Fig. 1 while supporting the holding device 3A. That is, the predetermined movement of the holding device 3A in this embodiment is a rotation movement about the first rotation axis A1. In this embodiment, the orientation of the wafer T held by the holding device 3A with respect to the ion beam IB changes as the holding device 3A rotates about the first rotation axis A1.

[0036] In addition, a first interlocking body 4A whose operation is controlled by the device control unit 5 is disposed in the first processing chamber 2A. The first interlocking body 4A in this embodiment is connected to a main body 12 of a first driving device 10A, and is configured to be able to reciprocate on a predetermined first transfer path R1 formed in the first processing chamber 2A. Any configuration may be adopted for driving the first interlocking body 4A, such as a configuration using a ball screw.

[0037] The main body 12 of the first driving device 10A and the holding device 3A move on the first transport path R1 together with the first interlocking moving body 4A. Therefore, when the first interlocking moving body 4A moves on the first transport path R1, the wafer T held by the holding device 3A also moves along the first transport path R1. In the ion beam irradiation device 1, the first interlocking moving body 4A moves on the first transport path R1, so that the wafer T held by the holding device 3A crosses the ion beam IB with the processing surface facing the ion beam IB. In this way, the wafer T moves so as to cross the ion beam IB, so that the irradiated surface of the wafer T is irradiated with the ion beam IB, and the wafer T is subjected to ion implantation processing.

[0038] 2, the holding device 3A includes a holder 3a that holds the wafer T, and a support 3b that supports the holder 3a. The holder 3a is, for example, an electrostatic chuck that electrostatically attracts the wafer T.

[0039] The holding device 3A further includes a support shaft 3c connected to the holding body 3a, and a rotary motor 3d connected to the support shaft 3c and rotating the support shaft 3c around the second rotation axis A2. The support body 3b is box-shaped, and the rotary motor 3d is housed inside the support body 3b. The support shaft 3c is disposed so as to penetrate a portion of the outer wall of the support body 3b, and the support body 3b rotatably supports the support shaft 3c. With this configuration, the holding body 3a is rotatably supported by the support body 3b via the support shaft 3c.

[0040] In the holding device 3A of this embodiment, when the rotation motor 3d is driven, the holder 3a rotates together with the support shaft 3c about the second rotation axis A2. Therefore, the ion beam irradiation device 1 can rotate the wafer T held by the holder 3a about the second rotation axis A2 by driving the rotation motor 3d.

[0041] Fig. 3 shows a state in which the holding device 3A is in an initial position Q1. In this embodiment, the initial position Q1 is the position of the holder 3a when the wafer T, which has been carried into the first processing chamber 2A from the outside, is placed on the holder 3a. Fig. 4 shows a state in which the holding device 3A is in a stop position Q2. In this embodiment, the stop position Q2 is the position of the holder 3a in a state in which the wafer T is stopped and directed toward the ion beam IB before the wafer T is irradiated with the ion beam IB.

[0042] In the ion beam irradiation apparatus 1 in this embodiment, the wafer T is carried into the first processing chamber 2A from the outside through a load lock chamber (not shown). After that, the wafer T is placed on the holder 3a at the initial position Q1 shown in FIG. 3 with the processing surface of the wafer T, which is the surface to be irradiated with the ion beam IB, facing upward (Y direction in the figure), and is held by the holding device 3A. At this time, the rotation motor 3d may be driven as necessary to rotate the wafer T by a required amount around the second rotation axis A2. Then, the first driving device 10A is driven to rotate the holding device 3A around the first rotation axis A1, and the holding device 3A is stopped at the stop position Q2 shown in FIG. 4. This operation causes the processing surface of the wafer T to be directed toward the ion beam IB. After that, the first interlocking operating body 4A operates, and the wafer T crosses the ion beam IB, so that the wafer T is irradiated with the ion beam IB.

[0043] 2, the first driving device 10A is directly or indirectly connected to a side surface of the support 3b of the holding device 3A and includes a first driving member 14A that drives the holding device 3A. The first driving member 14A is a shaft body that is driven by the power output by the stepping motor 11 and is rotatable about a first rotation axis A1.

[0044] The first driving member 14A in this embodiment is indirectly connected to the holding device 3A via a rotation introducer 15 arranged in a case 19 described later and a connecting shaft body 16 that connects the rotation introducer 15 to a side surface of the support body 3b of the holding device 3A. The first driving member 14A, the connecting shaft body 16, and the support body 3b are configured to operate together, and when the first driving member 14A rotates about the first rotation axis A1, the holding device 3A also rotates by the same amount as the first driving member 14A. The first driving member 14A may be directly connected to the holding device 3A. In this case, for example, a configuration in which a seal member is disposed in the area where the first driving member 14A penetrates the case 19 may be adopted.

[0045] The first driving device 10A is provided with a first power transmission unit 20A that is interposed between the stepping motor 11 and the first driving member 14A and transmits the power output from the stepping motor 11 from the stepping motor 11 to the first driving member 14A.

[0046] The first power transmission unit 20A in this embodiment includes a driving pulley 21, a driven pulley 22, and a belt 23 wound around the driving pulley 21 and the driven pulley 22. The belt 23 is made of a rubber material and has elasticity.

[0047] The first driving device 10A has an output shaft 17 that outputs the rotational motion of the stepping motor 11, and the output shaft 17 is connected to a driving pulley 21 so that their rotation axes coincide with each other. In addition, a first driving member 14A is connected to a driven pulley 22 so that their rotation axes coincide with each other, and the driven pulley 22 and the first driving member 14A are configured to rotate integrally around a first rotation axis A1.

[0048] In the first driving device 10A, when the stepping motor 11 is driven to output power, the driving pulley 21 rotates together with the output shaft body 17, and the belt 23 moves with the rotation of the driving pulley 21. The driven pulley 22 rotates following the movement of the belt 23. As the driven pulley 22 rotates, the first driving member 14A and the holding device 3A rotate about the first rotation axis A1. In this way, the power output by the stepping motor 11 is transmitted to the first driving member 14A and the holding device 3A via the first power transmission unit 20A. The first power transmission unit 20A is not limited to a specific configuration, and the above-described configuration of this embodiment is merely an example.

[0049] The first driving device 10A further includes a first encoder 18A capable of acquiring position information of the first driving member 14A. The first encoder 18A is capable of detecting the rotation angle or rotation position of the first driving member 14A as the amount of movement of the first driving member 14A, and a commonly known encoder is used.

[0050] When the stepping motor 11 operates and then stops, the first encoder 18A acquires stop position information related to the position where the first driving member 14A stops, and transmits the acquired stop position information to the control unit 13. The stop position information in this embodiment is information on the rotation angle or rotation position of the first driving member 14A acquired by the first encoder 18A. When the first driving member 14A moves linearly, the first encoder 18A detects the amount of linear displacement of the first driving member 14A caused by the operation of the stepping motor 11. In this case, the stop position information is the amount of linear movement of the first driving member 14A.

[0051] The first encoder 18A can detect the amount of movement of the first driving member 14A, but the first driving member 14A and the holding device 3A operate together, so the first encoder 18A can be considered to detect the amount of movement of the holding device 3A.

[0052] The stepping motor 11 used in this embodiment is a well-known one, and has a structure in which the rotation angle of the stepping motor 11 is proportional to the number of pulse signals (number of pulses). In other words, the movement amount (rotation angle) of the output shaft body 17 is proportional to the number of pulses input to the stepping motor 11. Therefore, the movement amount (rotation angle) of the first driving member 14A is ideally proportional to the number of pulses input to the stepping motor 11.

[0053] The control unit 13 transmits a pulse signal having a number of drive pulses required to rotate the first driving member 14A by a predetermined angle around the first rotation axis A1 to the stepping motor 11, thereby operating the stepping motor 11. As described above, the first driving member 14A and the holding device 3A operate integrally. Therefore, the control unit 13 may be regarded as transmitting a pulse signal having a number of drive pulses required to rotate the holding device 3A by a predetermined angle around the first rotation axis A1 to the stepping motor 11.

[0054] The first driving device 10A includes a case 19 that houses the stepping motor 11, the output shaft 17, the first power transmission unit 20A, and the first driving member 14A, and the inside of the case 19 is an atmospheric pressure environment. In the first driving device 10A, the case 19, and the first driving member 14A, the stepping motor 11, the first power transmission unit 20A, and the first encoder 18A housed in the case 19 constitute a main body 12. In this embodiment, the first encoder 18A is disposed inside the case 19, i.e., in an atmospheric pressure environment, but may be disposed in a vacuum environment. In this embodiment, the first encoder 18A may be disposed, for example, outside the case 19, which is in a vacuum environment, and configured to directly detect the amount of movement of the connecting shaft 16. Even in this case, the connecting shaft 16 operates integrally with the first driving member 14A, so that the first encoder 18A acquires stop position information of the first driving member 14A.

[0055] Furthermore, the control unit 13 can perform a pulse number changing process for changing the set number of drive pulses based on the stop position information received from the first encoder 18A. In other words, the control unit 13 does not always transmit a constant number of drive pulses to the stepping motor 11, but can change the number of drive pulses appropriately based on the stop position information.

[0056] When the moving operation of the holding device 3A is repeated, it is considered that, for example, the components constituting the first power transmission unit 20A, such as the driving pulley 21, the belt 23, and the driven pulley 22, will wear out or deform, and the belt 23 will expand or contract. In this case, if a constant number of driving pulses is always input to the stepping motor 11, it is considered that the stopping position of the first driving member 14A will change over time.

[0057] In contrast, the first driving device 10A of this embodiment can stop the first driving member 14A at a specified position or within a specified range with high accuracy by the control unit 13 always or as necessary correcting the number of driving pulses based on the stop position information.

[0058] Next, the operation of the ion beam irradiation device 1 will be described. In the ion beam irradiation device 1, first, the wafer T is carried in through a load lock chamber (not shown) connected to the first processing chamber 2A. At this time, as shown in Fig. 1, the first interlocking operating body 4A and the holding device 3A are in a start position P that avoids the ion beam IB. The wafer T carried in the first processing chamber 2A is placed on the holding body 3a and then held by the holding device 3A with the surface to be processed facing upward (Y direction in the figure).

[0059] Thereafter, the control unit 13 transmits a pulse signal to the stepping motor 11 for driving the stepping motor 11, thereby driving the stepping motor 11. The pulse signal transmitted at this time has a preset number of drive pulses as the number of pulses required for the holding device 3A to perform a predetermined moving operation, that is, for the holding device 3A to rotate by a predetermined angle about the first rotation axis A1 and move from the initial position Q1 to the stop position Q2.

[0060] The number of drive pulses is the number of pulses calculated as being necessary to rotate the holding device 3A from the initial position Q1 to the ideal stop position Q2. In other words, even if the stepping motor 11 is driven by a pulse signal having the number of drive pulses, the holding device 3A does not necessarily stop at the expected stop position Q2. There are various possible reasons why the holding device 3A does not stop at the expected stop position Q2, such as, for example, the expansion and contraction of the elastic belt 23, backlash of the gears (not shown) that constitute the first power transmission unit 20A, and increased wear of each part, and there is no need to be limited to a specific cause.

[0061] When the stepping motor 11 is driven, the power output by the stepping motor 11 is transmitted to the holding device 3A via the first power transmission unit 20A, and the holding device 3A rotates. Then, the holding device 3A stops at the stop position Q2 shown in FIG. 4 with the processing surface of the wafer T facing the ion beam IB.

[0062] When the driving of the stepping motor 11 stops, the first encoder 18A measures the amount of movement of the first driving member 14A and transmits the measurement result to the control unit 13 as stop position information of the first driving member 14A. Then, the control unit 13 judges whether the first driving member 14A has stopped within a predetermined range. Since the first driving member 14A rotates around the first rotation axis A1 together with the holding device 3A, it is possible to judge whether the holding device 3A has stopped within a predetermined range by judging whether the first driving member 14A has stopped within a predetermined range.

[0063] The predetermined range in this embodiment is, for example, a range in which it can be determined that the ion beam IB may be continuously irradiated onto the wafer T. In other words, the predetermined range is a range in which it can be determined that the processing surface of the wafer T held by the holding device 3A is facing the ion beam IB in an appropriate direction.

[0064] Figure 5 shows the relationship between the movement amount α (displacement angle α) of the first driving member 14A when the holding device 3A rotates from the initial position Q1 to the stop position Q2, and the irradiation angle β, which is the angle between the ion beam IB and the normal direction of the irradiated surface of the wafer T. In the ion beam irradiation apparatus 1, in order to perform an appropriate ion implantation process on the wafer T, a range of irradiation angles β at which it is determined that the wafer T may be irradiated with the ion beam IB is calculated in advance, and an allowable movement amount α of the first driving member 14A is set corresponding to this range.

[0065] More specifically, as shown in Fig. 5, an allowable illumination angle range J (β1≦β≦β2) is defined as the range of the allowable illumination angle β, and an allowable movement amount range K1 (α2≦α≦α1) as the allowable range of the movement amount α is set according to the allowable illumination angle range J. Note that β0 included in the allowable illumination angle range J shown in Fig. 5 is the ideal value of the illumination angle β. Also, α0 included in the allowable movement amount range K1 is the value of the movement amount α when the illumination angle β=β0, and is the ideal value of the movement amount α.

[0066] In addition, the movement amount allowable range K1 is divided into a first allowable range K2 (α3≦α≦α4) that encompasses the movement amount α=α0, and a second allowable range K3 (α2<α<α3 and α4<α<α1) that is within the movement amount allowable range K1 but outside the first allowable range K2.

[0067] The first permissible range K2 is a range in which the first driving member 14A stops at an ideal position or a position close to the ideal position and it is considered that there is no need to change the number of driving pulses, while the second permissible range K3 is a range in which the first driving member 14A stops within an acceptable range but it is considered that there is a need to change the number of driving pulses.

[0068] When the movement amount α of the first driving member 14A is within the second permissible range K3, ions can be implanted into the wafer T, but the deviation from the ideal movement amount α0 is large. Therefore, if the first driving device 10A is repeatedly operated without changing the number of driving pulses, there is a risk that the movement amount α will thereafter deviate from the second permissible range K3.

[0069] In this case, the holding device 3A does not stop at an appropriate position for ion implantation into the wafer T, and irradiating the wafer T with the ion beam IB in this state may result in processing failure. Therefore, in this case, it is necessary to drive the first driving device 10A again. That is, in this embodiment, in order to suppress such a defect, a second allowable range K3 is provided for determining that the pulse number change process is necessary.

[0070] In this embodiment, after the stepping motor 11 operates and stops, the control unit 13 selects and performs one of the following first control, second control, and third control, depending on the stop position information received from the first encoder 18A.

[0071] (First control) When the control unit 13 determines that the first driving member 14A has stopped within the first allowable range K2, it performs a first control to maintain the stopped state of the first driving member 14A and transmit an authorization signal to the device control unit 5 to permit operation of the first interlocking operating body 4A. In the first control, the control unit 13 also determines that it is not necessary to change the number of driving pulses, that is, that a pulse number change process is not necessary.

[0072] (Second control) When the control unit 13 determines that the first driving member 14A has stopped within the second tolerance range K3, it maintains the stopped state of the first driving member 14A, sends an permission signal to the device control unit 5 to permit the operation of the first interlocking moving body 4A, and performs a second control to perform a pulse number change process to change the number of driving pulses to be input to the stepping motor 11 from the next time onwards.

[0073] (Third Control) When the control unit 13 determines that the first driving member 14A has not stopped within the movement amount allowable range K1, it performs a third control to drive the stepping motor 11 again so that the first driving member 14A stops within the first allowable range K2. In the third control, the stepping motor 11 may be driven to stop the first driving member 14A within the second allowable range K3. In other words, in the third control, the stepping motor 11 may drive the first driving member 14A to stop it within the range of the movement amount allowable range K1.

[0074] When the control unit 13 performs the third control, after the stepping motor 11 is stopped after being driven again, the control unit 13 again acquires the stop position information from the first encoder 18A. Then, according to the acquired stop position information, the control unit 13 again performs any one of the first control, the second control, and the third control.

[0075] When the control unit 13 performs the first control or the second control, the device control unit 5 receives an permission signal permitting the operation of the first interlocking body 4A and operates the first interlocking body 4A. Then, the first interlocking body 4A reciprocates multiple times on the first transport path R1, during which the ion beam IB is irradiated onto the processing surface of the wafer T held by the holding device 3A.

[0076] That is, the first control and the second control performed by the control unit 13 are both controls that determine that the first driving member 14A has stopped within the range of the movement amount allowable range K1, and continue to irradiate the wafer T with the ion beam IB.

[0077] However, if the first drive unit 10A stops within the second allowable range K3, if the first drive unit 10A is repeatedly operated without performing the pulse number change process as described above, it is considered that the first drive unit 10A will eventually stop outside the movement amount allowable range K1.

[0078] Therefore, in the second control, the control unit 13 performs a pulse number change process to recalculate the number of drive pulses based on the difference between the value of the movement amount α acquired as the stop position information and α0, which is the ideal value of the movement amount α. Then, from the next time onwards, the control unit 13 transmits a pulse signal having the recalculated number of drive pulses to the stepping motor 11.

[0079] When the first driving device 10A stops outside the range of the allowable movement amount K1, that is, when the control unit 13 performs the third control, it is necessary to drive the stepping motor 11 again to stop the first driving device 10A within the range of the allowable movement amount K1. In this case, the time required to perform the ion implantation process on the wafer T increases in order to drive the stepping motor 11 again, and as a result, the throughput of the ion beam irradiation device 1 decreases.

[0080] Therefore, in the ion beam irradiation device 1, it is required to prevent as much as possible the occurrence of an event in which the first driving device 10A stops outside the range of the movement amount allowable range K1. Therefore, in the ion beam irradiation device 1 of this embodiment, the control unit 13 performs the second control to suppress the occurrence of the event.

[0081] If a servo motor were used instead of the stepping motor 11 and the first encoder 18A were used as an external encoder for the servo motor, depending on the configuration of the first power transmission unit 20A, feedback control from the external encoder would be applied before the first driving member 14A stopped, driving the servo motor, etc., and it would take time to stop the first driving member 14A. In addition, there is a risk of a hunting phenomenon occurring.

[0082] Possible reasons why the first driving member 14A does not stop instantly after the servo motor is stopped include, for example, expansion and contraction due to the elasticity of the belt 23, or rattling due to backlash or increased wear of gears (not shown) that make up the first power transmission unit 20A.

[0083] In contrast, the first driving device 10A of this embodiment uses a stepping motor 11. Unlike a servo motor that is feedback-controlled until it stops at an appropriate position by a signal from an encoder, the stepping motor 11 stops with high precision in response to an input pulse signal. Therefore, the first driving device 10A can not only accurately control the position at which the holding device 3A is stopped, but also shorten the time required for the holding device 3A to stop after starting a predetermined movement operation, compared to when a servo motor is used.

[0084] The control unit 13 of this embodiment is configured to select and perform any one of the first control, the second control, and the third control based on the stop position information acquired from the first encoder 18A, but is not limited to this. The control unit 13 may be configured to select and perform any one of the first control and the second control, and may be configured to select and perform any one of a plurality of controls including the first control and the second control.

[0085] In addition, the control unit 13 may be configured to perform a pulse number change process each time to change the set number of drive pulses based on the stop position information obtained from the first encoder 18A, rather than selecting one of the multiple controls as described above.

[0086] The first driving device 10A and the vacuum device 1 equipped with the first driving device 10A can stop the first driving member 14A, which is driven by the power of the stepping motor 11, at a preset position or within a range with high accuracy. As a result, the first moving body 3A connected to the first driving member 14A is also stopped at a preset position or within a range with high accuracy.

[0087] In addition, since the first driving device 10A and the vacuum device 1 equipped with the first driving device 10A employ a stepping motor 11, even if there is a rattle or the like in the first power transmission unit 20A, the first driving member 14A can be stopped in a short time compared to the case of using a conventional servo motor.

[0088] The first driving device 10A and the vacuum device 1 equipped with the first driving device 10A can further perform a pulse number changing process in which the control unit 13 changes the set number of driving pulses based on the stop position information transmitted from the first encoder 18A. Therefore, even if the moving operation of the first moving body 3A is repeated and the stop position of the first driving member 14A is considered to change over time due to wear or deformation of the parts constituting the first power transmission unit 20A, for example, the first driving member 14A can be stopped at a predetermined position or within a predetermined range with high accuracy.

[0089] In this way, the first driving device 10A and the vacuum device 1 equipped with the first driving device 10A can precisely control the position at which the moving body is stopped, and can reduce the time required for the moving body to stop after starting a specified movement operation compared to the conventional method.

[0090] Also, the control unit 13 can be configured to select and perform one of a plurality of controls including the first control and the second control in response to the stop position information transmitted from the first encoder 18A as described above. For example, even if the stop position of the first driving member 14A is within a predetermined range, when it is estimated that the first driving member 14A is likely to stop outside the predetermined range in the next or subsequent operation, the second control that performs the pulse number change process is executed. This allows the first driving member 14A to continue to ensure high positioning accuracy.

[0091] Moreover, since the first driving member 14A can continue to ensure high positioning accuracy, the processing target T is processed in a state where it is positioned with high accuracy.

[0092] When the first power transmission unit 20A has an elastic part such as the belt 23, if a conventional servo motor is used, it takes time to converge the stop position of the first driving member 14A. In contrast, by adopting the configuration of this embodiment using the stepping motor 11, it becomes possible to stop the first driving member 14A within a predetermined range in a shorter time than in the past, even when the first power transmission unit 20A has an elastic part.

[0093] Next, a second driving device 10B according to a second embodiment of the present invention will be described. Among the components of the second drive device 10B, those common to the first drive device 10A of the first embodiment are given the same reference numerals as in the first embodiment, and description thereof will be omitted. 6, in the second embodiment, a holding device 3A for holding a wafer T is disposed in a second vacuum chamber 2B, the interior of which is kept at a high vacuum and into which an ion beam IB is introduced. In addition, a first atmospheric chamber 7A, the interior of which is kept under an atmospheric pressure environment, is provided below the second vacuum chamber 2B.

[0094] The second driving device 10B is disposed in the first atmospheric chamber 7A, except for a part of the second driving member 14B described later. The second driving device 10B is connected to the bottom surface of the support 3b of the holding device 3A and includes a second driving member 14B which is a shaft that rotates integrally with the holding device 3A around a third rotation axis A3 shown in Fig. 6. A hole is formed in the wall separating the second vacuum chamber 2B and the first atmospheric chamber 7A, through which the second driving member 14B passes, and a first seal member 7a is disposed in the hole.

[0095] The second driving device 10B includes a second power transmission unit 20B that transmits the power output by the stepping motor 11 to the second driving member 14B. The second power transmission unit 20B includes a first gear 24, a second gear 25, and a third gear 26. The first gear 24 is connected to the output shaft 17 so that their rotation axes coincide with each other. The second driving member 14B is connected to the third gear 26 so that their rotation axes coincide with each other.

[0096] In the second driving device 10B, when the stepping motor 11 is driven, the first gear 24 rotates together with the output shaft 17. Then, the second gear 25 meshing with the first gear 24 and the third gear 26 meshing with the second gear 25 each rotate, and the second driving member 14B rotates about the third rotation axis A3.

[0097] When the second driving member 14B rotates about the third rotation axis A3, the holding device 3A rotates together with the second driving member 14B. In the second embodiment, the first encoder 18A transmits the amount of movement (rotation angle) of the second driving member 14B rotated about the third rotation axis A3 as stop position information to the control unit 13 after the stepping motor 11 is driven and stopped.

[0098] The second driving device 10B includes a second interlocking body 4B whose operation is controlled by the device control unit 5 and which moves the second driving device 10B up and down along the Y direction in the figure. The second interlocking body 4B transports the second driving device 10B in the up and down direction, causing the wafer T held by the holding device 3A to cross the ion beam IB in the Y direction in the figure, whereby the wafer T is irradiated with the ion beam IB.

[0099] Next, a third driving device 10C according to a third embodiment of the present invention will be described. As shown in FIG. 7, in the third embodiment, a third driving device 10C is provided in a vacuum device 1 and moves a second movable body 3B arranged in a third vacuum chamber 2C, which is a transport chamber for the object to be processed T.

[0100] The third vacuum chamber 2C has a high vacuum environment inside. The third vacuum chamber 2C is connected to a second atmospheric chamber 7B having an atmospheric pressure environment inside. The third driving device 10C is disposed in the second atmospheric chamber 7B, except for a part of a third driving member 14C described later.

[0101] A second moving body 3B is disposed in the third vacuum chamber 2C, and a third driving member 14C that can move together with the second moving body 3B is connected to the second moving body 3B. A hole through which the third driving member 14C passes is formed in the wall that separates the third vacuum chamber 2C from the second atmosphere chamber 7B, and a second seal member 7b is disposed in the hole. A stepping motor 11 and a third power transmission unit 20C that transmits the power output by the stepping motor 11 to the third driving member 14C are housed in the second atmosphere chamber 7B.

[0102] The third power transmission unit 20C includes a ball screw 27 having a screw shaft 27a and a nut 27b that moves along one direction (the Z direction in the figure) on the screw shaft 27a, and a connecting member 28 that connects the nut 27b to the third driving member 14C.

[0103] In this embodiment, when the stepping motor 11 is driven, the ball screw 27 operates, and the third driving member 14C moves in one direction (the Z direction in the figure) together with the nut 27b and the connecting member 28. That is, when the stepping motor 11 is driven, the second moving body 3B moves in one direction (the Z direction in the figure).

[0104] The third driving device 10C includes a second encoder 18B that detects the amount of movement of the third driving member 14C in one direction after the stepping motor 11 is driven. After the stepping motor 11 operates and stops, the second encoder 18B transmits the amount of movement of the third driving member 14C in one direction (Z direction in the figure) as stop information to the control unit 13. In this embodiment, the second encoder 18B is disposed in the second atmosphere chamber 7B, but may be disposed in the third vacuum chamber 2C.

[0105] The movable body in the present invention may be disposed in a processing chamber in which a predetermined processing is performed on the processing object T, as disclosed in the first and second embodiments, or may be disposed in a transfer chamber provided in the vacuum device 1, as disclosed in the third embodiment.

[0106] In addition, the predetermined movement of the moving body in the present invention may be a predetermined rotational movement as disclosed in the first and second embodiments, or may be a linear movement as disclosed in the third embodiment. The predetermined movement of the first moving body 3A may be a combination of linear movement and rotational movement. The encoder of the present invention is not limited to one that detects the rotation angle of the driving member as disclosed in the first and second embodiments, but may be one that detects the linear movement amount of the driving member as disclosed in the third embodiment.

[0107] In addition, the present invention has been described assuming that the vacuum device 1 is an ion beam irradiation device, but the ion beam irradiation device is not limited to an ion implantation device, and may be, for example, a surface modification device that modifies the surface of an object by an ion beam. Therefore, the processing object T is also not limited to a wafer, and may be, for example, a glass substrate, a synthetic resin film, or a metal member formed into a predetermined shape.

[0108] Furthermore, the vacuum apparatus 1 is not limited to an ion beam irradiation apparatus. The vacuum apparatus 1 may be any apparatus, such as a deposition apparatus, that performs a predetermined process on the processing target T in a vacuum environment.

[0109] Furthermore, the present invention is not limited to the above-described embodiment and modified examples, and it goes without saying that various modifications are possible without departing from the spirit and scope of the present invention. [Explanation of symbols]

[0110] 1. Vacuum equipment (ion beam irradiation equipment) 2A First vacuum chamber (first processing chamber) 3A First moving body (holding device) 10A First Drive Unit 11 Stepping motor 13. Control Unit 14A First Drive Member 18A First Encoder 20A First Power Transmission Unit

Claims

1. A drive device used in a vacuum apparatus that performs a predetermined process on a processing object, the drive device moving a moving body arranged in a vacuum environment so that the moving body performs a predetermined moving operation, A driving member that is directly or indirectly connected to the moving body and moves the moving body; A stepping motor that outputs power to drive the driving member; a power transmission unit interposed between the stepping motor and the driving member and configured to transmit the power from the stepping motor to the driving member; A control unit for controlling the operation of the stepping motor; an encoder that acquires stop position information related to a position where the driving member stops as the stepping motor stops, and transmits the stop position information to the control unit; Equipped with the control unit is configured to input a pulse signal having a preset number of drive pulses as a number of pulses required for the moving operation to the stepping motor to operate the stepping motor, and then perform a pulse number changing process for changing the set number of drive pulses based on the stop position information. Drive unit.

2. The control unit: After operating the stepping motor, at least a first control for determining that the driving member has stopped within a predetermined range and determining that the pulse number change process is unnecessary, and for maintaining the driving member in a stopped state; a second control that determines that the driving member has stopped within the predetermined range and that the pulse number change process is necessary, and maintains the stopped state of the driving member and performs the pulse number change process; The control is configured to select one of a plurality of controls including The drive device according to claim 1 .

3. the movable body is a holding device that holds the processing object, 3. The drive device according to claim 1, wherein the moving operation is an operation of moving the holding device holding the processing object to a position where the processing is performed.

4. the power transmission unit has a power transmission member that transmits the power, The drive unit according to claim 1 or 2, wherein the power transmission member has elasticity.

5. A vacuum apparatus that performs a predetermined process on a processing object, the vacuum apparatus comprising: a driving device that moves a moving body arranged in a vacuum environment so as to perform a predetermined moving operation of the moving body, the driving device comprising: The drive device is A driving member that is directly or indirectly connected to the moving body and moves the moving body; A stepping motor that outputs power to drive the driving member; a power transmission unit interposed between the stepping motor and the driving member and configured to transmit the power from the stepping motor to the driving member; A control unit for controlling the operation of the stepping motor; an encoder that acquires stop position information related to a position where the driving member stops as the stepping motor stops, and transmits the stop position information to the control unit; Equipped with The control unit: a pulse signal having a preset number of drive pulses as a number of pulses required for the moving operation is input to the stepping motor to operate the stepping motor, and then a pulse number changing process is performed to change the set number of drive pulses based on the stop position information. Vacuum equipment.

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